The invention described herein relates generally to slapper detonators, and more particularly to improved slapper detonators of simple design and economical construction.
The slapper detonator, as described by J. R. Stroud in Lawrence Livermore Laboratory document UCRL-77639, "A New Kind of Detonator - The Slapper", dated Feb. 27, 1976, "operates by exploding a thin metal foil, which accelerates a plastic film across a gap to impact on a high-density secondary explosive". Traditionally, the thin metal foil, or bridge, is etched from a metal film on a dielectric substrate. The plastic film is comprised of polyester such as mylar, or polyimide such as kapton, and is placed over the bridge to act as the flyer. The gap is provided by a piece of plastic shim stock with a punched hole, called a barrel, that is bonded to the flyer film. Finally, an explosive pellet is placed over the hole in the barrel.
Dahn et al in U.S. Pat. No. 3,669,022 issued June 13, 1972 disclose a thin film device for use as a fuze or fuse. A thin insulating layer is disposed between a pair of conductive layers, with one of the conductive layers and the insulating layer having pin holes within which a bridging element of low density and low specific heat metal is disposed, so as to short circuit the conductive layers. Electrical energy supplied to the conductive layers vaporizes the metal in the pin holes. An explosive is disposed in intimate contact with the low density and low specific heat metal bridging element.
McCormick et al in U.S. Pat. No. 4,471,697 issued Sept. 18, 1984 teach a bidirectional slapper detonator that comprises a bridge element sandwiched between two barrel holders, with a sapphire barrel disposed in each holder. Flyers, comprised of the base or laminate upon which the layer of copper of which the bridge element is a part is disposed, are positioned between the bridge element and each of the barrels. Initiating pellets are placed adjacent to each barrel and barrel holder. The layer of copper is folded on itself around a separated, individual circuit insulator.
MacDonald et al in U.S. Pat. No. 4,602,565 issued July 29, 1986 disclose an exploding foil detonator in which an exploding bridge shears a foil and drives a piece of that foil against an explosive to detonate it. The electric current that operates the detonator flows through the detonator along an electrical conductor foil that enters and exits the detonator via distinctly separated paths.
Even though the slapper detonator, since its inception, has become a staple component of the art of detonator science, there remains a continuing need for improved slapper detonators of simple design and economical construction.